1. Field of the Invention
The present invention relates, in general, to amusement park rides such as dark rides that provide evacuation points upon loss of power, and, more particularly, to systems and methods for driving or propelling vehicles along a track in a dark or other amusement park ride so as to allow fewer evacuation points for vehicles on loss of power, e.g., by providing a drive or propulsion system that decouples from the vehicle upon loss of power allowing the vehicles to continue to travel to an evacuation point provided along the track.
2. Relevant Background
Amusement parks continue to be popular worldwide with hundreds of millions of people visiting the parks each year. Many rides incorporate a slower portion or segment to their rides to allow them to provide a “show” in which animation, movies, three-dimensional (3D) effects, audio, and other effects are presented as vehicles proceed through such show portions. For example, a roller coaster may be designed such that in a show portion dinosaurs attack vehicles, meteors fly toward the passengers, animatronic figures perform, and the like. The show may be designed based on the anticipated speed of the vehicle after it enters the show portion such that an effect such as 3D “attack” on the vehicle occurs precisely when the vehicle is adjacent to a portion of the display screens, speakers, and/or other show equipment. Other rides are designed such that the show includes jets, streams, and other water effects that require knowledge of vehicle position and speed to achieve desired effects such as water passing near passengers without striking the passengers or vehicle. Other rides are used to tell stories, and it is desirable to control the speed or pace of the vehicles during show sections of the ride so the passengers can enjoy the set, which may include special effects that are sensitive to or synchronized to vehicle speed (e.g., a multimedia presentation may actually be intentionally distorted such that it appears normal to passengers in a vehicle when the vehicle is moving at a particular speed but when the vehicle is moving too fast or too slow the distortion may be seen).
Ride designers or engineers are given the task of producing unique attractions that provide show portions while also providing rides that are less costly to operate and maintain. Typically, amusement park rides are designed to provide drive systems for moving vehicles in a manner that tightly controls the speed of the vehicles along the track and, particularly, in show portions. In a conventional ride, a mechanical coupling is provided between the vehicle and the drive or propulsion mechanism such as in a dark ride used mainly to provide a show with themed display. Upon loss of power, the vehicle is locked or frozen to or on the track. In designing an amusement park ride, it is preferred that the track and adjacent platforms provide adequate evacuation points for passengers even when power is lost for the drive or propulsion. As a result, new designs for rides often will include evacuation points at every point along the track, which can significantly limit the track or ride design or can drive up attraction costs.
In one particular case, there have been a number of concepts generated for new suspended and self-powered ride systems that would be useful in dark ride attractions. Many of these have failed to receive capital funding for a number of reasons including costs associated with meeting existing evacuation requirements within the amusement park ride industry. It has proven difficult to meet the demand for a powered vehicle that can have its speed controlled throughout a ride rather than simply being periodically paced as is the case with roller coasters while also providing full evacuation capability upon power loss, e.g., not acceptable to have a vehicle be coupled to a section of track where there is no evacuation platform or ready access. There are also demands for rides to provide gravity drops, cause variable speeds, include steeper inclines and declines than typically provided on dark rides, and other operating parameters to increase guest satisfaction, but these design features also contribute to increased costs and are difficult to address with existing ride drive or propulsion systems.